一种改进型无刷直流电机转子位置检测技术

分析了无位置传感器无刷直流电机控制系统中反电势检测方法存在的问题，提出了改进措施，通过检测相电流来确定悬空相，设计了低通滤波器，降低了脉宽调制所引起的高频干扰；针对滤波器的相移,提出了一种既可以补偿滤波器相移又可以检测过零点的检测电路。给出了硬件电路和软件流程。实验证明了这些改进措施的有效性。

An Improved Detection of Rotor Position of Brushless DC Motor

To improve the efficiency of detection of BEMF Zero-crossing for the sensorless control of BLDCM, the paper firstly analyses the practical problems of the method, with that, the detection of the free phase by detecting phase current was presented and a filter for reducing the high frequency disturbance of PWM was designed. In order to eliminate the phase shift of the filter, an estimate circuit of compensating phase shift, including software flow char, was proposed, this circuit can also be used to detecting BEMF Zero-crossing. Finally the experimental result shows those works are effectual.